硫系薄膜具有独一无二的辐照效应和红外光学性能，是制备大容量光存储和高精度光学器件以及中、远红外激光传输的理想材料。然而，硫系薄膜易氧化，强光辐照更会加剧氧化程度，对激光精确写入信息和结构以及材料本身的光学和化学性能造成不利的影响，因而迫切需要明确光致氧化反应机理及其与薄膜组成的关系。本课题将针对具有极为宽泛玻璃形成区的Ge-As-Se系统硫系薄膜，采用高分辨率X射线光电子光谱和红外透过光谱差谱表征薄膜光致氧化,并和暗室自然氧化进行比较研究；采用扫描电镜和原子力显微镜表征光致氧化产物和薄膜表面形貌变化；通过组分微调和原位毫秒动力学分析，系统研究薄膜光致氧化的机理，弥补国内外在硫系薄膜氧化过程动力学研究方面的空白，并在此基础上进一步探究光致氧化对薄膜光暗化、光漂白以及光膨胀等辐照效应的影响。课题的开展对实现硫系薄膜制备新型光学器件以及外场作用下红外光学材料在被动光学方面的应用具有重要意义。

Chalcogenide films exhibit unique photo-induced effects and wide infrared transmission window. They have been considered as promising materials for optical data storage, opto-electronic devices and infrared laser power delivery. However, chalcogenide films are prone to oxidation, especially when being exposed in air. The photo-oxidation is detrimental for precise writing optical functions in photonic chips based on chalcogenide films, and it will also influence the optical and chemical stabilities of the films. Thus the fundamental problems are what is the mechanism of the photo-oxidation given quite controversial arguments have presented nowadays and how it is related to the compositions of the films. The proposed project will systematically explore the photo-oxidation effect of the Ge-As-Se ternary system due to the extremely wide glass forming region. The photo-oxidation will be characterized by high resolution X-ray photoemission spectroscopy and differential infrared transmission spectrum, and it will be compared to the oxidation occurring in the dark condition. The surface morphology of the films will be monitored by scanning electron microscope and atomic force microscopy. The mechanism of photo-oxidation will be investigated by in-situ millisecond dynamics measurement for the first time, and the effects of the photo-oxidation on the photodarkening, photobleaching and photoexpansion will be studied. The present work is of interests and importance for both engineers designing opto-electronic devices with improved performance and for applications in passive infrared optics.